Selection effectiveness of lodging tolerance by using pushing resistancefor improving rice cultivar adapted to direct sowing culture in floodedpaddy fields [Chinese]

摘要

This study was undertaken to find the selection effectiveness of lodging tolerance by using pushing resistance for improving rice cultivar adapted to direct sowing culture in flooded paddy fields. The lines used in the experiment were F, and F, breeding lines of Aoinokaze//Lemont/Hinohikari; 47 lines and Yumehikari//Lemont/Hinohikari; 29 lines that were medium maturity lines. There was a significant negative correlation between the pushing resistance of F-4 lines in transplanting culture and lodging degree of F-5 lines in direct sowing culture. Even though the selection rate of pushing resistance in F-4 was changing from 10% to 40% there was a distinct difference in lodging degree under direct sowing culture in F-5. A few F-6 lines selected by using pushing resistance in transplanting culture were superior in lodging tolerance and yielding ability under direct sowing culture. There were comparatively few deviations of yielding ability and grain quality by using pushing resistance for the selection of lodging tolerance in an early generation. These results lead to the conclusion that it is possible to breed high lodging tolerance cultivar adapted to direct sowing culture by using pushing resistance under transplanting culture in an early generation.